In the oil and gas industry, as well as in the mining, water, and geothermal industries, samples are brought to the surface during drilling of wellbores to determine what substances may be found in a wellbore. For example, mud including chemicals, rock, and soil from the wellbore may be brought to the surface and tested in a lab. Also, samples of rock formations from the wellbore may be brought to the surface (e.g., sidewall coring, full coring, etc.) for inspection and testing.
Knowing the chemical composition of the materials in a wellbore may be helpful in determining whether to keep drilling a wellbore, or in determining whether a wellbore that is in use remains suitable for its intended purpose. For example, it may be helpful to know whether certain hydrocarbons associated with oil and gas are present in a wellbore to determine whether to keep drilling for oil or gas.
Substantial investments in time, effort and money may routinely be made to bring material from a wellbore to the surface for inspection and testing. For example, wellbore drilling may often be halted in order to deploy a specialized bit configured for obtaining a sample of a rock from the wellbore (i.e., full coring). Such investments continue, however, because the information obtained thereby may be of sufficient value to justify the investment.